Though prices may sway customers one way or another, a blogger at Tainted Green points out that since the Volt runs partially on gasoline -- as opposed to the all-electric Volt -- some customers

Tainted Green: Urban dwellers who live in apartments usually store their cars in parking garages or on the street where there is no readily available electrical outlet. In that case a purely electric vehicle like the Nissan LEAF becomes a tough sell. The Chevy Volt still accepts gasoline and so would still be an option for a typical urban lifestyle...Right now there is no extensive charging infrastructure in the United States even close to the ubiquity of gas stations. That means longer trips are unlikely in a Nisaan LEAF while the Chevy Volt could easily still generate excellent mileage (compared to conventional combustion engines) using gasoline as its only energy source during travels.